(1) Field of the Invention
The field of the invention is music. More specifically, the field is automated creation of harmony for melody and analysis of music. The best Implementation is in software form.
Definitions
The terms “harmony rules” and “rules of harmony” each refer to the body of knowledge accumulated over recent centuries by specialists and others in the field of music which knowledge is recognized as preferred practice in the use of harmony. The rules are exemplified in the book “Longmans' Music Course Part II—Harmony and Counterpoint”, by T. H. Bertenshaw, Longmans Green and Co., Ltd., London (1926).
The musical term “note” implies, inter alia, its pitch (some writers use the term “tone” for note).
Terms distinguished by an initial upper case are defined for the easier reading of this document:                “Implementation” refers to “mode for carrying out the present invention”.        “Melody” refers to a time series of notes having at least one note.        “Harmonizer” refers to harmonizer means in the present invention for creating an accompaniment.        “Rules” refers to the harmony rules accessible by and used by the present invention. See “Representative List of Harmony Rules” appended to the description.        “Controls” refers to parameters determined by the user of the Harmonizer. Controls direct the Harmonizer process. Controls are fixed for the duration of harmonizing a Melody.        “Preferences” refers to parameters not being Controls some of which are determined by the user of the Harmonizer and others of which are preset by the Harmonizer. Preferences direct the harmonizing process. The Harmonizer can weaken (compromise) Preferences.        “Preceding Melody Note” means melody note at which a chord was most recently created preceding the current melody note.        
(2) Background Art
Traditional Methods
Music has long been harmonized manually. That is, whether composers enter the notes or chords into a machine, such as a computer, or write them by hand, they rely on their knowledge of the rules of harmony, or on what they think sounds good to their own ear. It is a tedious process, it is possible to miss the best solution, and it is difficult to comprehend simultaneously all the many rules. It is easy to find errors in compositions of even the great composers, including Bach; and Mendelssohn is noted (Bertenshaw, cited) for breaking the rules.
It is recognized that breaking the rules is sometimes deliberate in order to achieve a particular effect, and the best Implementation does not preclude this being done manually after harmonizing.
Traditional methods of harmonizing include manual iterative procedures in which, upon the seemingly satisfactory creation of a chord, the composer advances to create the next. The composer will often have a pre-conception of what chord should be used, but may find that, after attempting various permutations of the chord parts, the Rules cannot be accommodated. If this remains the case after trying several of the better choices of chords, the composer, rather than trying a poorer choice, will retreat to the previous chord to try alternatives there. If several such iterations are necessary, the composer may try something more radical at an earlier chord in the hope of finding a solution more readily. The Harmonizer formalizes each of these processes, with the qualification, however, that even at the point of trying “something more radical” it will not break the Rules. None of the following inventions discloses this kind of iteration.
Another tedious and error prone manual process is the recognition of species, degree, inversion, mode, intervals and semitones of chords in music. The present invention discloses features which derive these chord parameters from the music using that part of the Harmonizer which analyzes chords, and which present them to the user and which annotate music with chord notation and figured bass.
Where a composer wishes to create or alter harmony manually, there is difficulty in recalling and applying the many rules of harmony, as already stated. The present invention discloses features which display breaches of the rules to the user using that part of the Harmonizer which analyzes chords according to the Rules.
Comparison with other Inventions
Citations                U.S. Pat. No. 5,525,749 Aoki; Eiichiro        U.S. Pat. No. 5,496,962 Meier; Sidney K.; Briggs; Jeffrey L.        U.S. Pat. No. 5,451,709 Minamitaka; Junichi        U.S. Pat. No. 4,982,643 Minamitaka; Junichi        U.S. Pat. No. 4,926,737 Minamitaka; Junichi        U.S. Pat. No. 6,124,543 Aoki; Eiichiro        U.S. Pat. No. 5,760,325 Aoki        U.S. Pat. No. 5,418,325 Aoki et al.        U.S. Pat. No. 5,883,326 Goodman et al.        U.S. Pat. No. 6,369,311 Iwamoto; Kazuhide        U.S. Pat. No. 5,850,051 Machover et al.        U.S. Pat. No. 5,003,860 Minamitaka        U.S. Pat. No. 6,060,655 Minamitaka; Junichi        U.S. Pat. No. 5,322,966 Shimaya; Hideaki        
The following comparisons with other inventions are based only upon the present inventor's understanding of them and are made in good faith.
Comparison with U.S. Pat. No. 5,525,749 Aoki; Eiichiro
The invention of U.S. Pat. No. 5,525,749 is described as a composition/arrangement assistant, in which a set of notes (referred to as tones) based on the melody note and the melody tonality (scale and mode) is presented to the user who then selects notes from that set for the other voices of the arrangement. Compliance with the rules of harmony, except for a few mentioned below, is left to the judgement of the user.
The present invention differs in that formal chords, characterized by degree, mode, species and inversion, are developed successively from internal chord specifications. The present invention assigns notes to each voice without user involvement, assesses the chord, and reallocates the parts or chooses another chord if the former chord is unsatisfactory. The harmonizing of the Melody proceeds to completion without user interaction.
The invention of U.S. Pat. No. 5,525,749 prohibits consecutive (parallel) fifths and octaves and prohibits minor ninths from the melody. This can be done without a knowledge of the species of chords, and represents a very small portion of the rules of harmony developed over the recent centuries. The present invention is distinguished by its ability to identify chords by degree, mode, species and inversion, and by its ability to identify the distribution of chord parts amongst the voices. This information is essential as the present invention then proceeds to assess chords for their compliance with the many rules of harmony available to it.
The present invention is therefore distinguished in that it proceeds without user intervention and that it produces an accompaniment in accordance with the Rules.
Comparison with U.S. Pat. No. 5,496,962 Meier; Sidney K.; Briggs; Jeffrey L.
The invention of U.S. Pat. No. 5,496,962 creates a plurality of options, analyzes those options exhaustively, attributes weighting factors to those options, and chooses the “best”. Refer to “Chord Selection” below. The present invention accepts the first chord found which satisfies the Controls, the Preferences and the Rules, and looks further only if it later retreats to the current melody note.
The invention of U.S. Pat. No. 5,496,962 composes original music, employing randomness amongst other processes, whereas the present invention creates, without randomness, parts for voices to accompany an existing Melody that is provided by the user. With the same user settings, the present invention exhibits repeatability.
Comparison with U.S. Pat. No. 5,451,709 Minamitaka; Junichi
The invention of U.S. Pat. No. 5,451,709 is an automatic composer using (dynamic) databases of melody progressions and chord progressions and employing pattern matching in the creation of melodies and chords. Although the invention discloses repetition of processes in order to optimize choices, it is intended to compose and play in real time. Refer to “Real Time Devices” below. The testing referred to in its claim 13 is against conditions which have been set, apparently by the user. The invention does not refer to the rules of harmony, whereas the present invention relies heavily on them. Rather than having a database of preferred progressions, the present invention achieves good chord progression as a consequence of enforcing the many rules of harmony. Refer to “Chord Selection” below.
Comparison with U.S. Pat. No. 4,982,643 Minamitaka; Junichi
The comments on U.S. Pat. No. 5,451,709 apply here also. References to “rules” in the disclosure of this and the previous invention refer to the rules of a knowledge base (expert system) and not to harmony rules.
Comparison with U.S. Pat. No. 4,926,737 Minamitaka; Junichi
The invention of U.S. Pat. No. 4,926,737 is an automatic composer using a melody motif. It relies on a (dynamic) database of chord progressions. The earlier comments under U.S. Pat. No. 5,451,709 on rules and chord progression apply here. The invention of U.S. Pat. No. 4,926,737, as a composer, is naturally concerned with the development of a pleasing melody, and much is made of the detection of “non-harmonic tones”.
The user is involved in the selection of chords for Melody notes. By contrast, the present invention accepts a Melody from the user, and the quality and style of the harmony produced is naturally dependent on the quality and style of the Melody. There is no user intervention during processing.
Comparison with U.S. Pat. No. 6,124,543 Aoki; Eiichiro
The invention of U.S. Pat. No. 6,124,543 analyzes the melody to be accompanied and compares the melody with a melody example. Refer to “Melody Analysis” and “Use of Examples” below.
Comparison with U.S. Pat. No. 5,760,325 Aoki; Eiichiro
The invention of U.S. Pat. No. 5,418,325 derives rules from an input series of notes (melody). Chord selection is further based on examples of chord progressions. The invention appears to be an interactive device. Refer to “Melody Analysis” and “Chord Selection” below. There is no suggestion of revision of chord selections, whereas the present invention can revise the choice of chord. Refer to “Retreat and Revision” below.
Comparison with U.S. Pat. No. 5,418,325 Aoki et al.
The invention of U.S. Pat. No. 5,418,325 derives rules from an input series of notes (melody). Refer to “Melody Analysis” below. It describes a real time operation—refer to “Real Time Devices” below. It requires the input of at least one chord accompanying the input melody, and creates harmony by an assessment of non-harmonic notes, that is, passing notes and their allies. Refer to “Chord Selection” below.
Comparison with U.S. Pat. No. 5,883,326 Goodman et al.
The invention of U.S. Pat. No. 5,883,326 requires an example of melody and harmony. It derives rules by analysis from the example and applies them to a second melody (claim 1). Significantly, the outcome of applying the rules to the second melody is not stated in the claim. Refer to “Use of Examples” and “Chord Selection” below. All of the musical knowledge of the present invention is confined to fixed rules and tables. Refer also to “Real Time Devices” below. U.S. Pat. No. 5,883,326 refers to a class of inventions typified by U.S. Pat. No. 5,308,915 which make use of neural networks. Neural networks behave in a manner dissimilar to that of the present invention in that they learn from examples. The present invention has no learning capability.
Comparison with U.S. Pat. No. 6,369,311 Iwamoto; Kazuhide
The invention of U.S. Pat. No. 6,369,311 creates an accompaniment for a melody according to examples of other performances (compositions). Refer to “Use of Examples” below.
Comparison with U.S. Pat. No. 5,850,051 Machover et al.
The invention of U.S. Pat. No. 5,850,051 discloses a device responding to performances. Its distinguishing feature appears to be its capability of revising the operator's requirements by analysis of the operator's performance (the melody). Refer to “Melody Analysis” below. The invention of U.S. Pat. No. 5,850,051 discloses a real-time device. Refer to “Real Time Devices” below.
Comparison with U.S. Pat. No. 5,003,860 Minamitaka
The invention of U.S. Pat. No. 5,003,860 requires chords to be specified with the melody. Refer to “Chord Selection” below. It operates in real time. Refer to “Real Time Devices” below. The invention of U.S. Pat. No. 5,003,860 analyzes music input to determine key (changes), whereas the present invention does not—key and rhythm changes are explicit.
Comparison with U.S. Pat. No. 6,060,655 Minamitaka; Junichi
Refer to “Chord Selection” below. The invention of U.S. Pat. No. 6,060,655 requires an input of chord progression examples which evolves with use. Refer to “Use of Examples” below. The present invention assesses progression after the allocation of chord parts to voices.
Comparison with U.S. Pat. No. 5,322,966 Shimaya; Hideaki
The invention of U.S. Pat. No. 5,322,966 determines a chord type given a chord. Refer to “Chord Selection” below—the reverse process. The invention of U.S. Pat. No. 5,322,966 describes a real time operation. Refer to “Real Time Devices” below.
Melody Analysis
The present invention scans the Melody to assess the positions of beats and cadences. Beats and cadences are determined according to the duration of Melody notes, not to their pitch.
Rather than using rules, derived from the Melody or otherwise, for the selection of chords, the present invention takes each chord (specification) in order unconditionally, and only subsequently determines whether the chord should be rejected. The present invention analyzes the melody in combination with the harmony created, for compliance with the Rules, rather than to determine the style or nature of the melody.
Chord Selection
The present invention does not use rules to select chords for the melody, but rather selects from fixed tables chord specifications according only to the degree of the current melody note and the current mode of the melody. It constructs harmony from the chord specification, accounting for the melody note only in the formation of doubles, and only then tests the harmony against a fixed set of rules. Rather than selectively choosing acceptable chords, the present invention takes all chords and rejects unacceptable ones by analysis.
Use of Examples
The present invention uses no example melodies, performances or compositions. Whereas there is an extensive set of harmony rules considered in the art as correct practice, breaches of the rules can be found in the works of most composers. The use of examples from which to derive rules is therefore likely to propagate those breaches. In the context of a different albeit similar composition, those breaches may produce harmony inferior to that obtained in the present invention complying with the Rules.
Retreat and Revision
The present invention, when unable to harmonize a melody note according to Preferences, Controls and Rules, retreats to the Preceding Melody Note to revise the harmony there.
Real Time Devices
Because earlier harmony has already been sounded, real time devices cannot retreat along melody notes to revise earlier harmony, whereas retreat to revise earlier harmony is a significant feature of the present invention. The present invention is unsuited to real time use.
Summarising the Comparisons
The present invention appears to be unique in distinguishing harmony rules that must be complied with, from preferences that may be compromised. Its use of a comprehensive set of harmony rules as a significant component in the process of harmonizing appears to be unique. The present invention appears to be unique in its capability, when unable to select suitable harmony, to retreat to an earlier melody note to revise the choice of harmony there. The revision of earlier harmony gives the present invention a distinct advantage over others.
The present invention appears to be unique in its repeatability for given Melody, Controls and Preferences. There is no random process in the present invention.